In this paper, we set an object of study in the desert steppe in Ningxia, based on the field sampling and laboratory analysis. The characteristics of the fractal dimension of the soil and the relationship between fractal dimension and soil properties were studied. The results showed that:（1）there was more fine grained soil after enclosure. The clay（＜2 μm）content increased significantly in 0-10 cm, 10-20 cm and 20-40 cm soil layers（P＜0.05）.The silt sand（2-50 μm）content increased significantly in 0-10 cm soil layer（P＜0.05）. The sand（50-250 μm）content decreased in 0-10 cm, 10-20 cm soil layer（P＜0.05）.（2）Soil nutrients accumulated after enclosure. The organic carbon, TN, TP, alkalihydrolyzable nitrogen, available phosphorus content of soil were higher. In 0-10 cm soil layer, the organic carbon, TN, TP, alkalihydrolyzable nitrogen, available phosphorus content increased by 177.70%, 155.70%, 60.11%, 120.42%, and 179.40%, respectively. In 10-20 cm soil layer, the soil organic carbon, TN, TP, available phosphorus content increased by 202.80%,36.50%, 27.78% and 37.30%, respectively. The soil nutrient change is not significant in 20-40 cm soil layer（P＞0.05）. Obviously, enriched nutrients were distributed mainly in the 0-20 cm layer and concentrated in 0-10 cm layer（P＜0.05）.（3）In the enclosed plot, the fractal dimension of soil is of between 2.64-2.69, and the fractal dimension of the outside fence is 2.59-2.64. Compared with outside fence, the fractal dimension of soil in the enclosed plot increased significantly in 0-10 cm and 10-20 cm（P＜0.05）.（4）The soil fractal dimension and soil particle size distribution, the organic carbon, TN, TP, alkalihydrolyzable nitrogen, available phosphorus content all showed a linear relationship. The results show that fractal dimension can be used as a comprehensive index to measure soil fertility, soil structure and soil restoration.